 |
Claims  |
|
|
What is claimed is:
1. A gas burning apparatus comprising:
a burner means for burning a combustible gas;
a nozzle for supplying combustible gas to the burner means;
a flow rate control means for controlling the amount of the combustible gas
to be g-supplied to the nozzle;
a gas pressure detecting means for detecting the pressure of the
combustible gas supplied between the flow rate control means and the
nozzle;
a thermal power setting means for setting the combustion amount of the
combustible gas in the burner means;
a central control means, connected to the thermal power setting means and
the gas pressure detecting means, for setting the amount of the
combustible gas to be supplied to the burner means to a predetermined
value by driving the flow rate control means in response to a signal
outputted from the gas pressure detecting means, so that the combustion
amount in the burner means corresponds to a burning state set by the
thermal power setting means.
2. A gas burning apparatus as defined in claim 1, wherein gas is introduced
into a pressure sensing portion of the gas pressure detecting means via a
duct disposed between the flow rate control means and the nozzle and via a
flow rate restricting portion.
3. A gas burning apparatus as defined in claim 1, wherein the flow rate
control means comprises: a reducing means for varying the flow rate of the
combustible gas to be supplied to the nozzle; and a driving means for
driving the reducing means, so that when a gas pressure detected by the
gas pressure detecting means in a state in which the reducing means is
closed to the greatest extent does not reach a predetermined position
corresponding to a value set by the thermal power setting means, the
central control means stops the opening and closing operation of the
reducing means to be performed by the driving means at a predetermined
closing limit position.
4. A gas burning apparatus as defined in claim 3, wherein said reducing
means for performing thermal power adjustment comprises a needle and a
needle receiver disposed so as to control the flow rate of gas flowing
through a gap therebetween, wherein said needle and needle receiver are
provided with a plurality of flow rate control sections for adjusting a
flow rate of each of plural kinds of gases having different calorific
values in connection with the positional relationship between needle and
the needle receiver.
5. A gas burning apparatus as defined in claim 4, wherein an opening for
adjusting the flow rate of LPG to minimum is provided independently of the
reducing mechanism.
6. A gas burning apparatus as defined in claim 4, further comprising: a
driving means for driving the reducing means; and a position detecting
means for detecting the limit of the movable range of the reducing means
and a current position within the movable range, wherein the reducing
means is provided with a shock absorbing device at a limit point of the
movable range in a direction in which the flow rate of gas is reduced to a
minimum.
7. A gas burning apparatus as defined in claim 4, further comprising: a
position detecting means for detecting the limit of the movable range of
the reducing means and a current position within the movable range; and a
closing means for opening and closing a gas path, wherein the driving
means serves as means for driving the reducing means and the closing
means.
8. A gas burning apparatus as defined in claim 1, further comprising: a gas
kind change-over means for changing the kind of gas to be used; and a
position detecting means for detecting a reducing position in a region in
which the value of the reducing means of the flow rate control means
becomes maximum, wherein when the pressure of gas detected by the gas
pressure detecting means is lower than the predetermined gas pressure, the
central control means gives an alarm and/or stops the supply of
combustible gas to the burner means.
9. A gas burning apparatus as defined in claim 1, wherein the central
control means comprises: a drive speed determining means for controlling
the drive speed of the driving means so that the drive speed determining
means controls the drive speed of the driving means according to the
degree of the difference between the predetermined pressure of gas
corresponding to a thermal power set by the thermal power setting means
and the pressure of gas detected by the gas pressure detecting means.
10. A gas burning apparatus as defined in claim 1, further comprising: a
gas kind change-over means, wherein when the pressure of gas detected by
the gas pressure detecting means is higher than a maximum gas pressure of
a certain kind of gas set by the gas kind change-over means in setting a
maximum thermal power by the thermal power setting means, the central
control means drives the flow rate control means so as to set the pressure
of gas detected by the gas pressure detecting means to the maximum gas
pressure set by the gas kind change-over means.
11. A gas burning apparatus as defined in claim 1, further comprising: a
burner calorie change-over means for setting a maximum combustion amount
corresponding to the combustion performance of each burner so that the
central control means corrects the value of gas pressure equivalent to a
minimum combustion amount corresponding to the maximum combustion amount
of each burner set by the burner calorie change-over means.
12. A gas burning apparatus as defined in claim 1, further comprising: a
gas kind change-over means for changing the kind of gas, wherein the
central control means decides the kind of gas set by the kind change-over
means, and a minimum gas pressure equivalent to a minimum thermal power of
the thermal power setting means is set in advance in the central control
means depending on the kind of gas.
13. A gas burning apparatus as defined in claim 1, wherein the flow rate
control means comprises: a closing means for opening and closing a gas
path, and the central control means comprises: a storing means for storing
the pressure of gas applied to the gas pressure detecting means if the
pressure of gas is within a predetermined value provided that the closing
means is in a closed state; and a gas pressure determining/compensating
means for altering and correcting a reference value by assuming that the
pressure of gas stored in the storing means is at atmospheric pressure.
14. A gas burning apparatus as defined in claim 1, wherein the flow rate
control means comprises: a closing means for opening and closing the gas
path, and the central control means comprises: a storing means for storing
the pressure of gas to be applied to the gas pressure detecting means if
the pressure of gas is within a predetermined value provided that the
closing means is in a closed state so that an alarm is sounded when the
pressure of gas applied to the gas pressure detecting means exceeds a
predetermined value provided that the closing means is in a closed state.
15. A gas burning apparatus as defined in claim 1, wherein the flow rate
control means comprises: a closing means for opening and closing a gas
path, and the central control means comprises: a storing means for storing
the pressure of gas applied to the gas pressure detecting means if the
pressure of gas is within a predetermined value provided that the closing
means is in a closed state so that combustion is stopped when the pressure
of gas applied to the gas pressure detecting means exceeds a predetermined
value provided that the closing means is in a closed state.
16. A gas burning apparatus, as defined in claim 1, comprising a plurality
of burning apparatuses, to which gas is supplied from one gas cut-off
valve.
17. A gas burning apparatus as defined in claim 1, wherein the flow rate
control means comprises: a reducing means for varying the flow rate of the
combustible gas to be supplied to the nozzle; driving means for driving
the reducing means; a position detecting means for detecting the limit of
the movable range of the reducing means and a current position within the
movable range; and a closing means for opening and closing the gas path,
the driving means serving as means for driving the reducing means and the
closing means; and
the driving means and a closing portion of the closing means being spaced
from each other when the closing means is closed.
18. A gas burning apparatus, as defined in claim 1, comprising a plurality
of burning apparatuses, wherein the flow rate control means of each
burning apparatus comprises: a reducing means for varying the flow rate of
the combustible gas to be supplied to the nozzle; a driving means for
driving the reducing means; a position detecting means for detecting the
limit of the movable range of the reducing means and a current position
within the movable range; a closing means for opening and closing the gas
path;
and wherein the central control means comprises: a drive speed determining
means for controlling the drive speed of the driving means of the flow
rate control means; and an integrated drive determining means for
performing an integrated control over the drive of each of a plurality of
the independent flow rate control means;
the integrated drive determining means being operated in a predetermined
priority order when the difference between the pressure of gas
corresponding to a thermal power set by the thermal power setting means
and the pressure of gas supplied by the gas pressure detecting means is
detected to be smaller than a predetermined value in the burning
operations of a plurality of burning apparatuses.
19. A gas burning apparatus as defined in claim 1, further comprising: a
display means for displaying the set state of combustion; and a state
display determining means, provided on the central control means, for
determining the performance of the gas burning apparatus by operating a
specific key so that the state display determining means allows the gas
pressure detected by the gas pressure detecting means to be displayed by
the display means.
20. A gas burning apparatus comprising:
a burner means for burning combustible gas;
a nozzle for supplying combustible gas to the burner means;
a flow rate control means, for controlling the amount of the combustible
gas to be supplied to the nozzle, comprising: a reducing means, for
varying the flow rate of combustible gas to be supplied to the nozzle; a
driving means for driving the reducing means; and a position detecting
means for detecting the limit of the movable range of the reducing means
and a current position within the movable range;
a thermal power setting means for setting the combustion amount of the
combustible gas in the burner means; and
a central control means for driving the flow rate control means by a signal
outputted from the position detecting means so as to move the flow rate
control means to a reducing position of the reducing means corresponding
to a thermal power set by the thermal power setting means, wherein:
the central control means comprises: a drive speed determining means for
controlling the drive speed of the driving means according to the distance
between a current position in the movable range of the reducing means and
a position of the reducing means driven by the driving means from the
current position when the thermal power setting means alters thermal
power.
21. A gas burning apparatus comprising:
a thermal power setting means for setting the thermal power;
a flow rate control means, having a specified number of flow rate states,
for adjusting the thermal power;
a state display determining means for determining the performance of the
gas burning apparatus;
a display means for displaying various states including the temperature of
a temperature sensor and cooking period of time;
a back-up power supply for supplying power during a service interruption;
and
a service interruption determining means for limiting or stopping the
display of the display means so as to save electric power during service
interruption.
22. A gas burning apparatus comprising:
a temperature detecting means for detecting the temperature of a pan
bottom;
a burner means for burning combustible gas;
a nozzle for supplying combustible gas to the burner means;
a flow rate control means, for controlling the amount of the combustible
gas to be supplied to the nozzle, comprising: a reducing means for varying
the flow rate of the combustible gas to be supplied to the nozzle; and
driving means for driving the reducing means; and a position detecting
means for detecting the limit of the movable range of the reducing means
and a current position within the movable range;
a thermal power setting means for setting the combustion amount of the
combustible gas in the burner means;
a central control means for driving the flow rate control means to a
predetermined position in response to a signal outputted from the position
detecting means so that the flow rate control means moves to a reducing
position of the reducing means corresponding to a thermal power set by the
thermal power setting means;
the central control means comprising: a equilibrium temperature determining
means for determining, based on a temperature supplied by the temperature
detecting means whether or not a temperature rise gradient is greater than
a specified value within a predetermined temperature range and whether or
not an equilibrium temperature state has been generated so as to determine
if the temperature detecting means has become defective and stop the
operation of the gas burning apparatus when the equilibrium temperature
determining means has determined that the equilibrium temperature state
has been generated and that the position detecting means has determined
that the flow rate control means is at a maximum thermal power position.
23. A gas burning apparatus comprising:
a temperature detecting means for detecting the temperature of a pan
bottom;
a burner means for burning combustible gas;
a nozzle for supplying combustible gas to the burner means;
a flow rate control means for controlling the amount of the combustible gas
to be supplied to the nozzle;
a gas pressure detecting means for detecting the pressure of the
combustible gas supplied between the flow rate control means and the
nozzle;
a thermal power setting means for setting the combustion amount of the
combustible gas in the burner means;
a central control means, connected to the thermal power setting means and
the gas pressure detecting means, for setting the amount of the
combustible gas to be supplied to the burner means to a predetermined
pressure by driving the flow rate control means in response to a signal
outputting from the gas pressure detecting means, so that the combustion
amount in the burner means corresponds to a burning state set by the
thermal power setting means;
the central control means comprising: a equilibrium temperature determining
means for determining, based on a temperature supplied by the temperature
detecting means whether or not a temperature rise gradient is greater than
a specified value within a predetermined temperature range and an
equilibrium temperature state has been generated so as to determine if the
temperature detecting means has become defective and stop the operation of
the gas burning apparatus when the equilibrium temperature determining
means has determined that the equilibrium temperature state has been
generated and that the secondary gas pressure is greater than a
predetermined gas pressure. |
|
 |
|
 |
Claims |
|
|
|
Description |
|
|
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a gas burning instrument and more
particularly to a gas burning apparatus providing a burning control
section suitable for various kinds of gases and a safe burning and
preventing a set burning amount from being varied irrespective of the
fluctuation in the pressure of supplied gas. To this end, the pressure of
gas will be jetted from a nozzle is measured to control it in conformity
to a desired burning amount. The present invention also relates to a gas
burning apparatus capable of easily deciding the failure of a sensor
adapted for detecting the temperature of a pan bottom.
2. Description of the Related Arts
FIGS. 25 through 27 show an example of a conventional gas burning apparatus
applied to a gas cooking apparatus. FIG. 25 is a perspective view showing
the conventional gas cooking apparatus. FIG. 26 is an enlarged view
showing an operation panel. FIG. 27 is a schematic view showing the
construction of an oven. As shown in FIG. 25, the gas cooking apparatus
comprises a burner 1, a temperature sensor 2, a pan holder 3, an
ignition/extinction button 4, a thermal power adjusting lever 5, a grill
portion 6, and an operation panel 7. The operation panel 7 as shown in
FIG. 26 comprises a display tube 8 for displaying a time/temperature, an
LED 9 for displaying various kinds of cooking modes, and a key 10 for
setting various kinds of cooking modes. For example, in setting a mode for
frying fish, vegetable or the like, an operator presses the key 10 and
sets a desired temperature by operating an UP key or a DOWN key 11 while
the operator is watching a numerical value displayed by the display tube
8. FIG. 27 is a schematic view showing the construction of the oven. An
ignition switch 18 is turned on when the ignition/extinction button 4 is
depressed, and electric current is supplied to a main electromagnetic
valve 12 and a temperature adjusting valve 14 via a control substrate 19.
Gas is fed to the burner 1 via the main electromagnetic valve 12, a hand
valve 13, the temperature adjusting valve 14, a bypass key 15, a thermal
power adjusting needle 16, and a main nozzle 17, with the maximum flow
rate of gas regulated. At the same time, an igniter 20 is turned on via
the control substrate 19 and an ignition plug 21 is discharged. Then, the
burner 1 starts burning and a thermocouple 22 receives heat from the
burner 1 and transmits thermoelectromotive force to the control substrate
19. In this manner, burning continues.
The thermal power adjusting lever 5 is operated to move the thermal power
adjusting needle 16 in adjusting thermal power. In this manner, combustion
amount is adjusted. Otherwise, the power supply of the temperature
adjusting valve 14 is turned on and off in automatically adjusting
temperature so as to regulate the combustion amount by the bypass key 15
or by the main nozzle 17.
In changing the kind of gas due to removal or the like, it is necessary to
exchange or adjust parts such as the bypass key 15, the thermal power
adjusting needle 16, the main nozzle 17, a governor for grill, and a
damper 23 for taking in primary air.
The conventional thermal power adjusting method has the following
disadvantages: 10 Thermal power is adjusted by the thermal power adjusting
needle 16 or switched from a strong degree to a weak degree or vice versa
by an electromagnetic valve. The burning amount is not measured or
controlled. When the pressure of supplied gas fluctuates, it is impossible
to adjust the burning amount to a constant value. Accordingly, the
allowable range of the pressure of the supplied gas is wide. For example,
in the case of 13A gas, minimum gas pressure is 100 mm H.sub.2 O; central
gas pressure is 200 mm H.sub.2 O; and maximum gas pressure is 250 mm
H.sub.2 O. Even though thermal power is reduced to 100 mm H.sub.2 O, it is
necessary for the thermocouple to secure an appropriate
thermoelectromotive force to prevent an accidental fire. As a result, the
gas burning apparatus is incapable of reducing thermal power to 40% of
safety factor. A rapid change occurs in the strength of flame because gas
is burnt strongly and weakly by a temperature adjusting valve in adjusting
temperature automatically, which gives a user discomfort. In addition, in
controlling thermal power by a strong thermal power or a weak thermal
power or by the burning period of time, the operation sounds of valves are
frequently generated, which is offensive to the ear.
If a pressure sensor fails and as a result, gas leakage occurs because
means for preventing the gas cooking apparatus from being fired has not
been devised.
Thermal power cannot be reduced to a small thermal power if foreign matter
has stuck to a gap of the mechanism of the flow rate control means.
A function of detecting an abnormal pressure of supplied gas is not
provided. The abnormal pressure is generated because gas is not supplied
sufficiently if an LPG bomb is vacant, a rubber pipe is bent or a cock is
half-opened. Therefore, for example, when two ovens are used, the thermal
power is weak or gas is ignited but extinguishes soon. A user cannot find
the reason easily and hence, telephone calls for repair.
In adjusting gas pressure while it is being detected by a gas pressure
sensor, it is necessary that thermal power adjusting period of time is set
to be short to prevent boil-over by performing a rough pressure adjustment
and a fine pressure adjustment in consideration of the correlation between
the pressure-adjusting accuracy of a reducing mechanism, the performance
thereof, and the capability of detecting gas pressure.
The pressures of supplied gases are different from each other in
conventional gas burning apparatuses. Depending on the kind of gas, the
maximum pressure is higher by 40% than the standard pressure. As a result,
the temperature of the gas cooking apparatus greatly increases or an
abnormal burning occurs due to an abnormal gas pressure.
A conventional two-oven burning apparatus has a small burner having a
combustion amount of approximately 2000 Kcal/h and a large burner having a
combustion amount of approximately 4000 Kcal/h. The minimum combustion
amount of each burner is approximately 400 Kcal/h and 500 Kcal/h,
respectively. When the burning amount of gas is reduced further, flame is
not formed and extinguishes. Therefore, large and small needles for
adjusting thermal power are used for each burner. Consequently, in
changing the kind of gas, parts exchanges are required by disassembling a
gas cock. In this case, a gas leakage or an erroneous parts exchange may
occur.
The minimum combustion amount is not constant because burning speeds and
caloric values are different from each other, respectively depending on
the kind of gas. Accordingly, it is necessary to provide a needle for
setting a minimum burning amount for each kind of gas burner. Thus, a
large number of parts and assembling parts are required to use a different
kind of gas. Hence, it is necessary to disassemble a gas mechanical block
in using a different kind of gas, which requires a skilled work and much
time. Accordingly, cost for using a different kind of gas is high.
In using the apparatus as an industrial measuring instrument to measure
combustion amount by the pressure sensor, which has not been
conventionally adopted, a zero point adjustment can be accomplished in the
beginning of use. But in the case of a gas oven, it is difficult for old
people or children to perform a zero point adjustment and in addition, an
incomplete combustion occurs.
It occurs that the function of the pressure sensor deteriorates with the
elapse of time and hence the apparatus cannot be used, which gives a user
inconvenience.
If the performance of the apparatus deteriorates with the elapse of time,
thermal power cannot be adjusted and a user has an inconvenience in using
it.
It is preferable to install a safety device on each burner to cut off gas
in consideration of the situation in which one of burning apparatuses
provided under each burner fails. But electric power is required in
proportion to the number of burners and the manufacturing cost is high.
When the thermal powers of a plurality of burners are simultaneously
adjusted by using the pressure sensor, the thermal powers thereof cannot
be simultaneously adjusted due to the relationship between the processing
speed of the microcomputer and the flow rate control means. It takes much
time to adjust thermal power individually. For example, if thermal power
is required to be reduced with food contained in a pan placed on one oven
being boiled, water in the pan boils over.
In checking the performance of the pressure sensor provided in a gas
burning apparatus, a specific checking tool is required in manufacturing
the gas burning apparatus. It takes time and labor to install the checking
tool on the apparatus and remove it therefrom. A service man does not
carry it with him. Therefore, there is problem with the use of the
checking tool.
Since conventional gas burning apparatuses do not comprise the pressure
sensor, a needle corresponding to each kind of gas is conventionally used.
The gas burning apparatus according to the present invention is provided
with a universal flow rate control means capable of adjusting city gas
ranging from a low Wobbe index to liquified petroleum gas (LPG).
The area through which gas flows is slight in the construction of the
universal flow rate control means adapted for the minimum flow rate
adjustment of LPG having the highest calorific value. Therefore, the
conventional reducing mechanism does not ensure a reliable control of the
flow rate of gas.
If dust sticks to the adjusting mechanism of the universal flow rate
control means, a countermeasure for preventing the adjusting mechanism
from being destroyed is required in consideration of thermal power cannot
be reduced to a predetermined value.
The above-described conventional gas oven is more expensive than other
conventional gas ovens because of construction. Therefore, it is necessary
to take a measure of using some functions of other gas ovens in common.
It is also necessary to take a measure so that the cut-off means gives rise
to a gas leakage due to the common use of some functions of both type.
It is necessary to adjust thermal power at a high speed so that the
universal flow rate control means can be easily used and does not give
inconvenience to a user.
Few conventional gas burning apparatuses need power supply and therefore,
can be used during service interruption. Unless the above-described
conventional gas burning apparatus can be used in during service
interruption, it does not sell well.
It occurs that a conventional detecting means is incapable of detecting the
defect of the temperature sensor depending on the content of defect.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a gas burning apparatus
having a burning control section suitable for various kinds of gases for
safe burning.
It is another object of the present invention to provide a gas burning
apparatus preventing a set burning amount from being varied irrespective
of the fluctuation in the pressure of supplied gas.
It is still another object of the present invention to provide a gas
burning apparatus capable of easily deciding the failure of a sensor
adapted for detecting the temperature of a pan bottom.
In accomplishing these and other objects, as a first means, a gas burning
apparatus comprises: burner means for burning combustible gas; a nozzle
for supplying combustible gas to the burner means; flow rate control means
for controlling the amount of the combustible gas to be supplied to the
nozzle; gas pressure detecting means for detecting the pressure of the
combustible gas supplied between the flow rate control means and the
nozzle; thermal power setting means for setting the combustion amount of
the combustible gas in the burner means; central control means, connected
with the thermal power setting means and the gas pressure detecting means,
for adjusting the amount of the combustible gas to be supplied to the
burner means to a predetermined value by driving the flow rate control
means in response to a signal outputted from the gas pressure detecting
means, so that the combustion amount in the burner means corresponds to a
burning state set by the thermal power setting means.
As a second means, in the gas burning apparatus, gas is introduced into a
pressure sensing portion of the gas pressure detecting means via a duct
disposed between the flow rate control means and the nozzle and via a flow
rate restricting portion.
As a third means, in the gas burning apparatus, the flow rate control means
comprises: reducing means for varying the flow rate of the combustible gas
to be supplied to the nozzle; and driving means for driving the reducing
means, so that when a gas pressure detected by the gas pressure detecting
means in a state in which the reducing means is closed to the greatest
extent does not reach a predetermined position corresponding to a value
set by the thermal power setting means, the central control means stops
the opening and closing operation of the reducing means to be performed by
the driving means at a predetermined closing limit position.
As a fourth means, the gas burning apparatus further comprises: gas kind
change-over means for changing the kind of gas to be used; and position
detecting means for detecting a reducing position in a region in which the
value of the reducing means of the flow rate control means becomes
maximum. When the pressure of gas detected by the gas pressure detecting
means is lower than the predetermined gas pressure, the central control
means gives an alarm and/or stops the supply of combustible gas to the
burner means.
As a fifth means, in the Was burning apparatus, the central control means
comprises: drive speed deciding means for controlling the drive speed of
the driving means so that the drive speed deciding means controls the
drive speed of the driving means according to the degree of the difference
between the pressure of gas corresponding to a predetermined thermal power
set by the thermal power setting means and the pressure of Was detected by
the gas pressure detecting means.
As a sixth means, the gas burning apparatus further comprises: the gas kind
change-over means. When the pressure of gas detected by the gas pressure
detecting means is higher than a maximum gas pressure of a certain kind of
gas set by the gas kind change-over means in setting a maximum thermal
power by the thermal power setting means, the central control means drives
the flow rate control means so as to adjust the pressure of gas detected
by the gas pressure detecting means to the maximum gas pressure set by the
gas kind change-over means.
As a seventh means, the gas burning apparatus further comprises: burner
calory change-over means for setting a maximum combustion amount
corresponding to the combustion performance of each burner so that the
central control means corrects the value of gas pressure equivalent to a
minimum combustion amount corresponding to the maximum combustion amount
of each burner set by the burner calory change-over means.
As an eighth means, the gas burning apparatus further comprises: the gas
kind change-over means for changing the kind of gas. The central control
means decides the kind of gas set by the kind change-over means, and a
minimum gas pressure equivalent to a minimum thermal power of the thermal
power setting means is set in advance in the central control means
depending on the kind of gas.
As ninth means, in the gas burning apparatus, the flow rate control means
comprises: closing means for opening and closing a gas path, and the
central control means comprises: storing means for storing the pressure
(atmospheric pressure) of gas applied to the gas pressure detecting means
if the pressure of gas is within a predetermined value provided that the
closing means is in a closed state; and gas pressure deciding/compensating
means for altering and correcting a reference value by regarding that the
pressure of gas stored in the storing means is the atmospheric pressure.
As a ninth means, in the gas burning apparatus, the flow rate control means
comprises: closing means for opening and closing the gas path, and the
central control means comprises: storing means for storing the pressure
(atmospheric pressure) of gas to be applied to the gas pressure detecting
means if the pressure of gas is within a predetermined value provided that
the closing means is in a closed state so that an alarm is sounded when
the pressure (atmospheric pressure) of gas applied to the gas pressure
detecting means exceeds a predetermined value provided that the closing
means is in a closed state.
As a tenth means, in the gas burning apparatus, the flow rate control means
comprises: closing means for opening and closing a gas path, and the
central control means comprises: storing means for storing the pressure
(atmospheric pressure) of gas applied to the gas pressure detecting means
if the pressure of gas is within a predetermined value provided that the
closing means is in a closed state so that combustion is stopped when the
pressure (atmospheric pressure) of gas applied to the gas pressure
detecting means exceeds a predetermined value provided that the closing
means is in a closed state.
As a twelfth means, in the gas burning apparatus comprising a plurality of
burning apparatuses, gas is supplied from one gas cut-off valve to each
burning apparatus.
As a thirteenth means, in the gas burning apparatus the flow rate control
means comprises: reducing means for varying the flow rate of the
combustible gas to be supplied to the nozzle; driving means for driving
the reducing means; position detecting means for detecting the limit of
the movable range of the reducing means and a current position within the
movable range; and closing means for opening and closing the gas path. The
driving means serves as means for driving the reducing means and the
closing means; and the driving means and a closing portion of the closing
means are spaced from each other when the closing means is closed.
As a thirteenth means, in the gas burning apparatus comprising a plurality
of burning apparatuses, the flow rate control means of each burning
apparatus comprises: reducing means for varying the flow rate of the
combustible gas to be supplied to the nozzle; driving means for driving
the reducing means; for detecting the limit of the movable range of the
reducing means and a current position within the movable range; closing
means for opening and closing the gas path. The central control means
comprises: the drive speed deciding means for controlling the drive speed
of the driving means of the flow rate control means; and integrated drive
deciding means for performing an integrated control over the drive of each
of a plurality of the independent flow rate control means. The integrated
drive deciding means is operated in a predetermined priority order when
the difference between the pressure of gas corresponding to a thermal
power set by the thermal power setting means and the pressure of gas
supplied by the gas pressure detecting means is detected to be smaller
than a predetermined value in the burning operations of a plurality of
burning apparatuses.
As a fifteenth means, the gas burning apparatus further comprises: display
means for displaying the set state of combustion; and state display
deciding means, provided on the central control means, for deciding on the
performance of the gas burning apparatus by operating a specific key so
that the state display deciding means allows the gas pressure detected by
the gas pressure detecting means to be displayed by the display means.
As a sixteenth means, in the gas burning apparatus, the reducing mechanism
of reducing means for performing thermal power adjustment controls the
flow rate of gas of a low calorific value and a high calorific value by
means of a single driving means.
As a seventeenth means, in the gas burning apparatus, an opening for
adjusting the flow rate of LPG to minimum is provided independently of the
reducing mechanism.
As an eighteenth means, the gas burning apparatus further comprises:
driving means for driving the reducing means; and position detecting means
for detecting the limit of the movable range of the reducing means and a
current position within the movable range. The reducing means is provided
with a shock absorbing device at a limit point of the movable range in a
direction in which the flow rate of gas is reduced to a minimum.
As a nineteenth means, the gas burning apparatus further comprises:
position detecting means for detecting the limit of the movable range of
the reducing means and a current position within the movable range; and
closing means for opening and closing a gas path. The driving means serves
as means for driving the reducing means and the closing means.
As a twentieth means, a gas burning apparatus comprises: burner means for
burning combustible gas; a nozzle for supplying combustible gas to the
burner means; flow rate control means, for controlling the amount of the
combustible gas to be supplied to the nozzle, comprising: reducing means,
for varying the flow rate of combustible gas to be supplied to the nozzle;
driving means for driving the reducing means; and position detecting means
for detecting the limit of the movable range of the reducing means and a
current position within the movable range; and thermal power setting means
for setting the combustion amount of the combustible gas in the burner
means: central control means for driving the flow rate control means by a
signal outputted from the position detecting means so as to move the flow
rate control means to a reducing position of the reducing means
corresponding to a thermal power set by the thermal power setting means.
The central control means comprises: drive speed deciding means for
controlling the drive speed of the driving means according to the distance
between a current position in the movable range of the reducing means and
a position of the reducing means driven by the driving means from the
current position when the thermal power setting means alters thermal
power.
A 21st means, a gas burning apparatus comprises: thermal power setting
means for setting the thermal power; flow rate control means for adjusting
thermal power; state display deciding means for deciding on the
performance of the gas burning apparatus; display means for displaying
various states including the temperature of a temperature sensor and
cooking period of time; a back-up power supply for supplying power supply
in service interruption; and service interruption deciding means for
limiting or stopping the display of the display means so as to save
electric power in service interruption.
As a 22nd means, a gas burning apparatus comprises: temperature detecting
means for detecting the temperature of a pan bottom; burner means for
burning combustible gas; a nozzle for supplying combustible gas to the
burner means; rate control means, for controlling the amount of the
combustible gas to be supplied to the nozzle, comprising: reducing means
for varying the flow rate of the combustible gas to be supplied to the
nozzle; and driving means for driving the reducing means and position
detecting means for detecting the limit of the movable range of the
reducing means and a current position within the movable range; thermal
power setting means for setting the combustion amount of the combustible
gas in the burner means; central control means for driving the flow rate
control means to a predetermined position in response to a signal
outputted from the position detecting means so that the flow rate control
means moves to a reducing position of the reducing means corresponding to
a thermal power set by the thermal power setting means. The central
control means comprises: equilibrium temperature deciding means for
deciding based on a temperature supplied by the temperature detecting
means whether or not a temperature rise gradient is greater than a
specified value within a predetermined temperature range and whether or
not an equilibrium temperature state has been generated so as to decide
that the temperature detecting means has become defective and stop the
operation of the gas burning apparatus when the equilibrium temperature
deciding means has decided that the equilibrium temperature state has been
generated and that the position detecting means has decided that the flow
rate control means is at a maximum thermal power position.
As a 23rd means, a gas burning apparatus comprises: temperature detecting
means for detecting the temperature of a pan bottom; burner means for
burning combustible gas; a nozzle for supplying combustible gas to the
burner means; flow rate control means for controlling the amount of the
combustible gas to be supplied to the nozzle; gas pressure detecting means
for detecting the pressure of the combustible gas supplied between the
flow rate control means and the nozzle; thermal power setting means for
setting the combustion amount of the combustible gas in the burner means;
central control means, connected with the thermal power setting means and
the gas pressure detecting means, for adjusting the amount of the
combustible gas to be supplied to the burner means to a predetermined
pressure by driving the flow rate control means in response to a signal
outputted from the gas pressure detecting means, so that the combustion
amount in the burner means corresponds to a burning state set by the
thermal power setting means. The central control means comprises:
equilibrium temperature deciding means for deciding based on a temperature
supplied by the temperature detecting means whether or not a temperature
rise gradient is greater than a specified value within a predetermined
temperature range and an equilibrium temperature state has been generated
so as to decide that the temperature detecting means has become defective
and stop the operation of the gas burning apparatus when the equilibrium
temperature deciding means has decided that the equilibrium temperature
state has been generated and that the secondary gas pressure is greater
than a predetermined gas pressure.
According to the above-described construction, the following operations are
obtained.
The gas pressure deciding means detects pressure and the flow rate control
means adjusts pressure so that a gas pressure set by the thermal power
setting means is attained.
The flow rate restricting device provided on the gas inflow portion of the
pressure detecting section restricts the leakage amount of gas when the
pressure detecting section is damaged. In addition, if gas leaks even in a
slight amount, the leakage amount is indicated as an abnormal gas
pressure.
Even though a set gas pressure is not attained, the driving means is
stopped at the limit point of the movable range of the position deciding
means.
When the secondary gas pressure is less than the predetermined pressure at
the maximum thermal power position of the thermal power adjusting device,
an alarm is given or burning is stopped.
The drive speed of the flow rate control means is varied by the drive speed
deciding means. Therefore, when a strong thermal power is changed to a
weak thermal power, the flow rate control means is driven fast until
thermal power becomes weak. When the gas pressure is finely adjusted to
the set gas pressure, the flow rate control means is driven slowly.
When thermal power is set to the maximum, gas pressure is adjusted to the
maximum determined by the limit gas pressure determining means for
determining the maximum gas pressure.
Owing to the burner calory setting means and the weak (low) calory
compensating means, the burning amount of a burner can be changed. For
example, in changing the position of a burner of a large calory and that
of a burner of an intermediate calory to each other, a set pressure can be
altered in conformity to the capability of each burner without changing
the construction of the reducing mechanism. 8. The gas kind setting means
sets an optimum minimum gas pressure for each kind of gas in conformity to
its own combustibleness. Therefore, an optimum minimum gas pressure can be
finely set for each kind of gas.
Owing to the gas pressure deciding/compensating means, an error in
measurement due to the atmospheric temperature and aged deterioration can
be corrected, and a reference point, obtained when gas has no pressure,
can be always corrected.
Owing to the gas pressure deciding/compensating means, an error in
measurement which occurs due to the atmospheric temperature or aged
deterioration is alarmed.
The gas pressure deciding/compensating means is provided. Therefore, if the
gas sensing section often makes erroneous measurements it is incapable of
detecting an atmospheric temperature due to a measurement error or aged
deterioration, gas is not burnt for safety.
Since only one gas cut-off function is provided for a plurality of burning
apparatuses, electric power is consumed by the cut-off valve in a small
amount.
The driving means serves as the driving means of the gas cut-off means.
W | | |
